algorithm - Finding all possible combinations of numbers to reach …
2011年1月8日 · Here is a Java version which is well suited for small N and very large target sum, when complexity O(t*N) (the dynamic solution) is greater than the exponential algorithm. My version uses a meet in the middle attack, along with a little bit shifting in order to reduce the complexity from the classic naive O(n*2^n) to O(2^(n/2)) .
What is the difference between a heuristic and an algorithm?
2010年2月25日 · An algorithm is the description of an automated solution to a problem. What the algorithm does is precisely defined. The solution could or could not be the best possible one but you know from the start what kind of result you will get. You implement the algorithm using some programming language to get (a part of) a program.
What is the difference between an algorithm and a function?
An Algorithm usually refers to the method or process used to end up with the result after mathematical processing. A Function is a subroutine used to avoid writing the same code over and over again. They are different in their uses. For instance, there may be an Algorithm that is used for encrypting data, and a function for posting code to a ...
algorithm - What does O (log n) mean exactly? - Stack Overflow
2010年2月22日 · Algorithm 1: Algorithm 1 prints hello once and it doesn't depend on n, so it will always run in constant time, so it is O(1). print "hello"; Algorithm 2: Algorithm 2 prints hello 3 times, however it does not depend on an input size. Even as n grows, this algorithm will always only print hello 3 times.
algorithm - upper bound, lower bound - Stack Overflow
2013年2月4日 · Whatever the algorithm (merge sort, quick sort, etc), we cannot do better than this bound of \Omega(n log n). Lower bounds tell us, intuitively, how hard a particular problem is. When we talk about a specific algorithm, then we talk about upper bounds. For example, we say that the upper bound of bubble sort is O(n^2) and the upper bound of ...
algorithm - Difference between Big-O and Little-O Notation
2009年9月1日 · Stuff you know: A common way to classify algorithms is by runtime, and by citing the big-Oh complexity of an algorithm, you can get a pretty good estimation of which one is "better" -- whichever has the "smallest" function in the O! Even in the real world, O(N) is "better" than O(N²), barring silly things like super-massive constants and the like.
Algorithm to find duplicate in an array - Stack Overflow
2010年11月16日 · Your algorithm contains a buffer overrun. i starts with 0, so I assume the indexes into array A are zero-based, i.e. the first element is A[0] , the last is A[A.length-1] . Now i counts up to A.length-1 , and in the loop body accesses A[i+1] , …
Algorithm to return all combinations of k elements from n
2008年9月24日 · doc_180: Chase's algorithm is more complicated than the other algorithms but has the added benefit that each successive combination differs from the previous by just one element. This can be useful if the work that needs to be performed on each combination can be made faster if using the partial work of the previous combination.
algorithm - How do I check if a number is a palindrome ... - Stack …
2008年10月14日 · @Steve314 to describe an algorithm to convert an integer to a string, which of course requires you to understand modulo - no. Computing in the target number system, being able to add will do (think how you commonly convert from decimal to binary - being used to think computation means binary doesn't mean you can't do, e.g., decimal arithmetic (and you can …
Algorithm to search for a list of words in a text - Stack Overflow
2014年1月15日 · The algorithm builds a state machine from the words you want to search, and then runs the input text through that state machine, outputting matches as they're found. Because it takes some amount of time to build the state machine, the algorithm is best suited for searching very large bodies of text.